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CN-121986242-A - Air conditioner

CN121986242ACN 121986242 ACN121986242 ACN 121986242ACN-121986242-A

Abstract

The air conditioning device (1) includes a refrigerant circuit (6) and a control device (130). The refrigerant circuit (6) has a compressor (23), a radiator (64), an expansion valve (63), and an evaporator (24), and a refrigeration cycle for performing a heating operation for heating a room is performed by compressing a refrigerant to a critical pressure (Pc) or higher in the refrigerant circuit (6). A control device (130) controls the refrigerant circuit (6). The control device (130) controls the expansion valve (63) to regulate the refrigerant Temperature (TE) at the outlet (E) of the radiator (64), and controls the high pressure (Ph) of the refrigerant circuit (6) based on the temperature difference (Δtr) between the indoor Temperature (TR) and the target indoor temperature (TR 0).

Inventors

  • TAKEGAMI MASAAKI
  • Kimura Shangdeng

Assignees

  • 大金工业株式会社

Dates

Publication Date
20260505
Application Date
20240508
Priority Date
20230928

Claims (9)

  1. 1. An air conditioning apparatus, characterized in that: the air conditioning device comprises a refrigerant circuit (6) and a control device (130), The refrigerant circuit (6) has a compressor (23), a radiator (64), an expansion valve (63), and an evaporator (24), and the refrigerant circuit (6) compresses a refrigerant to a critical pressure (Pc) or higher to perform a refrigeration cycle for performing a heating operation for heating a room, The control device (130) controls the refrigerant circuit (6), The control device (130) controls the expansion valve (63) to regulate the refrigerant Temperature (TE) at the outlet (E) of the radiator (64) and controls the high pressure (Ph) of the refrigerant circuit (6) based on a temperature difference (Δtr) between an indoor Temperature (TR) and a target indoor temperature (TR 0).
  2. 2. An air conditioning apparatus according to claim 1, wherein: The control device (130) controls the compressor (23) to increase the high pressure (Ph) of the refrigerant circuit (6) when the temperature difference (DeltaTR) is greater than a first value.
  3. 3. An air conditioning apparatus according to claim 1 or 2, characterized in that: The control device (130) controls the compressor (23) to reduce the high pressure (Ph) of the refrigerant circuit (6) when the temperature difference (Δtr) is smaller than a second value.
  4. 4. An air conditioning apparatus according to any one of claims 1 to 3, wherein: the control device (130) controls the compressor (23) so that the high pressure (Ph) of the refrigerant circuit (6) becomes a lower limit value (Ph 1) of a control range when the temperature difference (DeltaTR) is smaller than a third value.
  5. 5. An air conditioner according to any one of claims 1 to 4, wherein: The refrigerant circuit (6) has a gas-liquid separator (25), an exhaust passage (41), and an on-off valve (42), The gas-liquid separator (25) is connected to the downstream side of the radiator (64), the gas-liquid separator (25) separates the refrigerant into a gaseous refrigerant and a liquid refrigerant, The exhaust passage (41) connects a gas reservoir (25 a) of the gas-liquid separator (25) with a suction side (23 i) of the compressor (23), The on-off valve (42) is provided on the exhaust passage (41), When the temperature difference (DeltaTR) is greater than a fourth value, the control device (130) causes the on-off valve (42) to open.
  6. 6. An air conditioning apparatus according to any one of claims 1 to 5, wherein: The refrigerant circuit (6) has a gas-liquid separator (25), the gas-liquid separator (25) is connected to the downstream side of the radiator (64), the gas-liquid separator (25) separates the refrigerant into a gaseous refrigerant and a liquid refrigerant, The specific enthalpy (he) of the refrigerant at the outlet (E) of the radiator (64) is less than the specific enthalpy (hc) at the critical point (C) of the refrigerant.
  7. 7. An air conditioner according to any one of claims 1 to 6, wherein: the heat sink (64) includes a first heat sink (64A) and a second heat sink (64B) connected in parallel with each other, The expansion valve (63) includes a first expansion valve (63A) corresponding to the first radiator (64A) and a second expansion valve (63B) corresponding to the second radiator (64B), The control device (130) controls the high pressure (Ph) of the refrigerant circuit (6) based on either or both of a first temperature difference (DeltaTRA) that is a temperature difference between an indoor Temperature (TRA) corresponding to the first radiator (64A) and a target indoor temperature (TR 0A) and a second temperature difference (DeltaTRB) that is a temperature difference between an indoor Temperature (TRB) corresponding to the second radiator (64B) and a target indoor temperature (TR 0B).
  8. 8. An air conditioning apparatus according to claim 7, wherein: the control device (130) controls the high pressure (Ph) of the refrigerant circuit (6) on the basis of the larger one of the first temperature difference (DeltaTRA) and the second temperature difference (DeltaTRB).
  9. 9. An air conditioning apparatus according to any one of claims 1 to 8, wherein: The refrigerant is carbon dioxide.

Description

Air conditioner Technical Field The present disclosure relates to an air conditioning apparatus. Background For example, as shown in patent document 1, various techniques relating to an air conditioner are disclosed. The air conditioner disclosed in patent document 1 includes a refrigerant circuit. The refrigerant circuit includes a compressor, a radiator, an expansion valve, and an evaporator, and performs a refrigeration cycle for performing a heating operation for heating an indoor space. Prior art literature Patent literature Patent document 1 Japanese patent laid-open publication No. 2021-055874 Disclosure of Invention Technical problem to be solved by the invention When the heating operation is performed using a refrigerant having a low critical pressure, the refrigerant is compressed to a critical pressure or higher. When the refrigerant is compressed above the critical pressure, it is difficult to control the temperature of the refrigerant because there is no condensation temperature of the refrigerant in the region above the critical pressure. Therefore, in the supercritical operation in which the refrigerant is compressed to the critical pressure or higher, it becomes difficult to adjust the indoor temperature, and it becomes difficult to adjust the temperature difference between the indoor temperature and the target indoor temperature. The purpose of the present disclosure is to adjust the temperature difference between the indoor temperature and the target indoor temperature in a heating operation in which the refrigerant is compressed to a critical pressure or higher to heat the indoor space in an air conditioning apparatus. Technical solution for solving the technical problems The first aspect of the present disclosure is directed to an air conditioning apparatus 1. The air conditioner 1 includes a refrigerant circuit 6 and a control device 130, the refrigerant circuit 6 having a compressor 23, a radiator 64, an expansion valve 63, and an evaporator 24, a refrigeration cycle for performing a heating operation for heating a room being performed in the refrigerant circuit 6 by compressing refrigerant to a critical pressure Pc or higher, the control device 130 controlling the refrigerant circuit 6, the control device 130 controlling the expansion valve 63 to adjust a refrigerant temperature TE at an outlet E of the radiator 64, and the control device 130 controlling a high pressure Ph of the refrigerant circuit 6 based on a temperature difference Δtr between a room temperature TR and a target room temperature TR 0. In the first aspect, in the air conditioner 1, the temperature difference Δtr between the indoor temperature TR and the target indoor temperature TR0 can be adjusted during the heating operation in which the indoor is heated by compressing the refrigerant to the critical pressure Pc or higher. In a second aspect of the present disclosure, the control device 130 controls the compressor 23 to increase the high pressure Ph of the refrigerant circuit 6 when the temperature difference Δtr is greater than a first value, on the basis of the first aspect. According to the second aspect, when the temperature difference Δtr between the indoor temperature TR and the target indoor temperature TR0 is greater than the first value, the indoor temperature TR can be increased by increasing the high pressure Ph of the refrigerant circuit 6. The temperature difference Δtr between the indoor temperature TR and the target indoor temperature TR0 can be reduced. In a third aspect of the present disclosure, on the basis of the first or second aspect, the control device 130 controls the compressor 23 to reduce the high pressure Ph of the refrigerant circuit 6 when the temperature difference Δtr is smaller than a second value. According to the third aspect, in the case where the temperature difference Δtr between the indoor temperature TR and the target indoor temperature TR0 is smaller than the second value, the load of the compressor 23 can be reduced by reducing the high pressure Ph of the refrigerant circuit 6. In a fourth aspect of the present disclosure, on the basis of any one of the first to third aspects, the control device 130 controls the compressor 23 to make the high pressure Ph of the refrigerant circuit 6 the lower limit value Ph1 of the control range when the temperature difference Δtr is smaller than a third value. According to the fourth aspect, in the case where the temperature difference Δtr between the indoor temperature TR and the target indoor temperature TR0 is smaller than the third value, the load of the compressor 23 is advantageously reduced by setting the high pressure Ph of the refrigerant circuit 6 to the lower limit value Ph 1. In a fifth aspect of the present disclosure, on the basis of any one of the first to fourth aspects, the refrigerant circuit 6 has a gas-liquid separator 25, a discharge passage 41, and an on-off valve 42, the gas-liquid separator 25 is connected to a down